Reconfigurable intelligent surface optimization and control signaling

The present Application is a 371 national stage filing of International PCT Application No. PCT/CN2022/084031 by SAHRAEI et al. entitled “RECONFIGURABLE INTELLIGENT SURFACE OPTIMIZATION AND CONTROL SIGNALING,” filed Mar. 30, 2022, which is assigned to the assignee hereof, and which is expressly incorporated by reference in its entirety herein.

The following relates to wireless communications, including reconfigurable intelligent surface (RIS) optimization and control signaling.

Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple-access communications system may include one or more base stations, each supporting wireless communication for communication devices, which may be known as user equipment (UE).

The described techniques relate to improved methods, systems, devices, and apparatuses that support reconfigurable intelligent surface (RIS) optimization and control signaling. For example, the described techniques provide for a first device associated with an RIS to identify a phase configuration for each reflective element of the RIS based on signaling received from a second device. Specifically, the first device may include an RIS corresponding to a set of reflective elements that may each be configured according to one of two possible phase configurations. Additionally, the first device may identify a first subset of the reflective elements corresponding to a first phase configuration (e.g., from the two possible phase configurations) and a second subset of the reflective elements corresponding to a second phase configuration (e.g., from the two possible phase configurations).

In one example, the first device may identify the first and second subsets based on receiving signaling from a second device indicating the subsets. For example, the second device may transmit signaling indicating a ratio of a first quantity of reflective elements in the first subset and a second quantity of reflective elements in the second subset. Here, the first device may identify first and second subsets that include reflective elements interleaved according to the ratio (e.g., indicated by the second device). In another example, the first device may identify the first and second subsets based on receiving signaling from the second device indicating a transmission beam of the second beam (e.g., used for signaling that is reflected by the first device from the second device to the third device). Here, the first device may identify the first and second subsets based on an angle of arrival at the first device and an angle of departure from the first device of the transmission beam. In either example, the first device may configure the first subset of reflective elements according to the first phase configuration and may configure the second subset of reflective elements according to the second phase configuration. Then, the first device may reflect transmissions between the second device and the third device.

A method for wireless communication at a first device including a set of multiple reflective elements is described. The method may include receiving signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and reflecting one or more signals from a second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

An apparatus for wireless communication at a first device including a set of multiple reflective elements is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and reflect one or more signals from a second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

Another apparatus for wireless communication at a first device including a set of multiple reflective elements is described. The apparatus may include means for receiving signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and means for reflecting one or more signals from a second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

A non-transitory computer-readable medium storing code for wireless communication at a first device including a set of multiple reflective elements is described. The code may include instructions executable by a processor to receive signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and reflect one or more signals from a second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the signaling may include operations, features, means, or instructions for receiving the signaling indicating a ratio of a first quantity of reflective elements in the first subset and a second quantity of reflective elements in the second subset.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving an indication of a set of integers corresponding to preconfigured ratio values, where receiving the signaling indicating the ratio includes receiving an indication of a first integer of the ratio from the set of integers and a second integer of the ratio from the set of integers, the first integer associated with the first subset and the second integer associated with the second subset.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the signaling indicating the ratio may include operations, features, means, or instructions for receiving a first integer of the ratio associated with the first subset and a second integer of the ratio associated with the second subset.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the signaling indicating the ratio may include operations, features, means, or instructions for receiving a first integer of the ratio associated with the first subset and a second integer indicating a difference between the first integer and a third integer of the ratio associated with the second subset.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the ratio includes a first quantity of reflective elements from the first subset of reflective elements and a second quantity of reflective elements from the second subset of reflective elements and the interleaved reflective elements include the first quantity of reflective elements having the first phase configuration interleaved with the second quantity of reflective elements having the second phase configuration.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting signaling indicating a capability of the first device, where receiving the signaling indicating the first subset and the second subset may be based on the signaling indicating the capability of the first device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the signaling indicating the capability of the first device may include operations, features, means, or instructions for transmitting signaling indicating that each of the set of multiple reflective elements may have the first phase configuration or the second phase configuration, or a quantity of the set of multiple reflective elements, or both.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for reflecting a first signal to the second device based on the first phase configuration for a third subset of reflective elements and the second phase configuration for a fourth subset of reflective elements and reflecting a second signal to the second device based on the first phase configuration for a fifth subset of reflective elements different than the third subset and the second phase configuration for a sixth subset of reflective elements different than the fourth subset, where receiving the signaling may be based on reflecting the first signal and the second signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first signal and the second signal include sounding reference signals (SRSs), physical random access channel (PRACH) signals, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first device includes an RIS.

A method for wireless communication at a first device is described. The method may include receiving signaling indicating a transmission beam of a second device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of the first device and an angle of departure from the set of multiple reflective elements, identifying, based on the angle of arrival and the angle of departure, a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, and reflecting one or more signals from the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

An apparatus for wireless communication at a first device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to receive signaling indicating a transmission beam of a second device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of the first device and an angle of departure from the set of multiple reflective elements, identify, based on the angle of arrival and the angle of departure, a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, and reflect one or more signals from the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

Another apparatus for wireless communication at a first device is described. The apparatus may include means for receiving signaling indicating a transmission beam of a second device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of the first device and an angle of departure from the set of multiple reflective elements, means for identifying, based on the angle of arrival and the angle of departure, a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, and means for reflecting one or more signals from the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

A non-transitory computer-readable medium storing code for wireless communication at a first device is described. The code may include instructions executable by a processor to receive signaling indicating a transmission beam of a second device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of the first device and an angle of departure from the set of multiple reflective elements, identify, based on the angle of arrival and the angle of departure, a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, and reflect one or more signals from the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the signaling indicating the transmission beam may include operations, features, means, or instructions for receiving signaling indicating an index associated with the transmission beam of the second device from a set of multiple transmission beams of the second device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the signaling indicating the transmission beam may include operations, features, means, or instructions for receiving signaling indicating a summation associated with the angle of arrival and the angle of departure of the transmission beam.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the transmission beam corresponds to a horizontal angle of arrival at the set of multiple reflective elements, a vertical angle of arrival at the set of multiple reflective elements, a horizontal angle of departure from the set of multiple reflective elements, and a vertical angle of departure from the set of multiple reflective elements and receiving the signaling indicating the transmission beam includes receiving a first summation associated with the horizontal angle of arrival, the vertical angle of arrival, the horizontal angle of departure, and the vertical angle of departure and a second summation associated with the vertical angle of arrival and the vertical angle of departure.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting signaling indicating a capability of the first device, where receiving the signaling indicating the transmission beam of the second device may be based on transmitting the signaling indicating the capability of the first device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the signaling indicating the capability of the first device may include operations, features, means, or instructions for transmitting signaling indicating that each of the set of multiple reflective elements may have the first phase configuration or the second phase configuration, signaling indicating a quantity of the set of multiple reflective elements, or both.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for reflecting a first signal to the second device based on the first phase configuration for a third subset of reflective elements and the second phase configuration for a fourth subset of reflective elements and reflecting a second signal to the second device based on the first phase configuration for a fifth subset of reflective elements different than the third subset and the second phase configuration for a sixth subset of reflective elements different than the fourth subset, where receiving the signaling indicating the transmission beam of the second device may be based on reflecting the first signal and the second signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first signal and the second signal include SRSs, PRACH signals, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first device includes an RIS.

A method for wireless communication at a first device is described. The method may include transmitting signaling to a second device including a set of multiple reflective elements, the signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and transmitting one or more signals to the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

An apparatus for wireless communication at a first device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to transmit signaling to a second device including a set of multiple reflective elements, the signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and transmit one or more signals to the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

Another apparatus for wireless communication at a first device is described. The apparatus may include means for transmitting signaling to a second device including a set of multiple reflective elements, the signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and means for transmitting one or more signals to the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

A non-transitory computer-readable medium storing code for wireless communication at a first device is described. The code may include instructions executable by a processor to transmit signaling to a second device including a set of multiple reflective elements, the signaling indicating a first subset of reflective elements corresponding to a first phase configuration and a second subset of reflective elements corresponding to a second phase configuration, where the first subset of reflective elements and the second subset of reflective elements include interleaved reflective elements of the set of multiple reflective elements and transmit one or more signals to the second device based on the first phase configuration for the first subset of reflective elements and the second phase configuration for the second subset of reflective elements.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the signaling may include operations, features, means, or instructions for transmitting the signaling indicating a ratio of a first quantity of reflective elements in the first subset and a second quantity of reflective elements in the second subset.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for transmitting a set of integers corresponding to preconfigured ratio values, where transmitting the signaling indicating the ratio includes transmitting an indication of a first integer of the ratio from the set of integers and a second integer of the ratio from the set of integers, the first integer associated with the first subset and the second integer associated with the second subset.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the signaling indicating the ratio may include operations, features, means, or instructions for transmitting a first integer of the ratio associated with the first subset and a second integer of the ratio associated with the second subset.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the signaling indicating the ratio may include operations, features, means, or instructions for transmitting a first integer of the ratio associated with the first subset and a second integer indicating a difference between the first integer and a third integer of the ratio associated with the second subset.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the ratio includes a first quantity of reflective elements from the first subset of reflective elements and a second quantity of reflective elements from the second subset of reflective elements and the interleaved reflective elements include the first quantity of reflective elements having the first phase configuration interleaved with the second quantity of reflective elements having the second phase configuration.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving signaling indicating a capability of the second device, where transmitting the signaling indicating the first subset and the second subset may be based on receiving the signaling indicating the capability of the first device.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, receiving the signaling indicating the capability of the first device may include operations, features, means, or instructions for receiving signaling indicating that each of the set of multiple reflective elements may have the first phase configuration or the second phase configuration, signaling indicating a quantity of the set of multiple reflective elements, or both.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving a first signal reflected by the second device based on the first phase configuration for a third subset of reflective elements and the second phase configuration for a fourth subset of reflective elements and receiving a second signal reflected by the second device based on the first phase configuration for a fifth subset of reflective elements different than the third subset and the second phase configuration for a sixth subset of reflective elements different than the fourth subset, where transmitting the signaling may be based on reflecting the first signal and the second signal.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first signal and the second signal include SRSs, PRACH signals, or a combination thereof.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the second device includes an RIS.

A method for wireless communication at a first device is described. The method may include transmitting signaling indicating a transmission beam of the first device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of a second device and an angle of departure from the set of multiple reflective elements and transmitting, to the second device, one or more signals via the transmission beam based on transmitting the signaling indicating the transmission beam.

An apparatus for wireless communication at a first device is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to transmit signaling indicating a transmission beam of the first device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of a second device and an angle of departure from the set of multiple reflective elements and transmit, to the second device, one or more signals via the transmission beam based on transmitting the signaling indicating the transmission beam.

Another apparatus for wireless communication at a first device is described. The apparatus may include means for transmitting signaling indicating a transmission beam of the first device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of a second device and an angle of departure from the set of multiple reflective elements and means for transmitting, to the second device, one or more signals via the transmission beam based on transmitting the signaling indicating the transmission beam.

A non-transitory computer-readable medium storing code for wireless communication at a first device is described. The code may include instructions executable by a processor to transmit signaling indicating a transmission beam of the first device, the transmission beam corresponding to an angle of arrival at a set of multiple reflective elements of a second device and an angle of departure from the set of multiple reflective elements and transmit, to the second device, one or more signals via the transmission beam based on transmitting the signaling indicating the transmission beam.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, transmitting the signaling indicating the transmission beam may include operations, features, means, or instructions for transmitting signaling indicating an index associated with the transmission beam of the first device from a set of multiple transmission beams of the first device.